I've been thinking about a 4 player modular control panel for a long time. I started out with pretty complicated ideas, and was never satisfied. I have finally come down to a very simple one, and I wanted to run it by you guys before I start cutting into wood:

Here's the basic layout.

Rendition of what it might look like if I had 3 friends.

This should show how big it will be in front of my 27" wide cabinet.

Here are what some modules look like.
I have a 2 player version more or less completed. It will be easy to remove the 2 player panel and plop in this 4 player version for nights when several guests come over.
The corners are rounded, so that everyone can shift around to find a balance between being to close to each other and comfort on the controls.
It's very important to me that I have a decent Karate Champ Vs. layout.
It's also very important to keep it as small as possible.
I tried to make sure that there was plenty of room so that players can rest the palm of their "button pressing hand" on solid wood no matter where they are standing.
(* edit *) The biggest problem that I can see is that the space is just too tight for 4 trackballs, particularly for frantic games like Soccer or Atari Football (the only 4P trackball Mame games). Short of building a 4 player cocktail cabinet like the original, there's really nothing I can do about that. (* /edit *)
Am I overlooking anything obvious? Can you guys offer any suggestions for improvements? All comments welcome.
Thanks,
Jake